Steels and alloys having elevated chromium content



desired with addition also of zirconium in quandeclare that what I claim is:

U1-u"r*1a: sures-PATENTOFF CE- I I 4 2,197,955 I sri-mts AND ALLOYS navm'e ELEVATED cnnomum con-ram Emanuel Valenta, Pilsen, Czechoslovakia, assignor, by mesne assignments, to Electro-Metal- V lurgical Company, New York, N. Y., a corporation of West Virginia a No Drawing. Application March at, 1938, Serial No. 197,728. In Czechoslovakia October 12 2 Claims. (Cl. 75-126) Steels and alloys having essentially a content the mechanical strength values, more particularof 5-30% of chromium and -3% of. carbon are ly in thecase of the bending strength, and in the characterised by high resistivity towards heat stability during temperature changes; it prevents, and corrosion, which in many casesis not atfor example, the appearance of cracks in the tainable with any other compositionof steels and proximity of welds. Very good results have been 5 alloys of this type. Their applicability in prac-' obtained, more particularly in the case of a contice, however, is very much limited by the grain tent of 0.35% of carbon, but an extensive imcoarseness which appears more particularly in provement is also obtained'in the-case of higher the case of cast pieces, this grain coarseness recarbon contents. sulting in a reduction of all mechanical strength This influence is particularly apparent in the 10 values, in the case of temperature changes, for case of alloys and steels which contain further example during welding, giving rise to the ready additional elements, such as for example silicon, formation of cracks. aluminium, copper, nickel and the like, individ- These great disadvantages are avoided accordually or in any desired combinations upto 5%. I 5 ing to the invention by adding to the steelsand Having now particularly described and ascer alloys-of this type 0.05-0.5% of nitrogen together tained the nature of my said invention and in with ODS-0.5% of titanium in any combination, if whatmanner the same is to be performed, I-

titles of ODS-0.5%. The common addition of 1. An alloy containing 5 to 30% chromium-an o titanium and nitrogen, with in certain cases the effective amount to 3% carbon, 0.05 to 0.5% nitrosimultaneous presenceof zirconium as well, has gen, 0.05 to 0.5% titanium and the remainder a considerable influence on making the texture iron. 1 i flner'than has been obtained. by mere presence 2. An alloy as defined in claim 1, wherein the y of titanium ornitrogen alone. The texture imcarbon content does not exceed 0.35%. v a provement is shown by a substantial increase in I f EMANUEL VALENTA. g5 

